Alternatively, pick a mosfet with a higher Vgs rating but designed for 5V gate drive, such as TSM2313CX.
Perhaps PMV48XP then?
Looks OK to me. The Vgs rating of that P-channel mosfet is only 8V, uncomfortablly close to the 6V drive it is getting, so it is probably better to spit the 2K2 resistor into 2 x 1K and drive the gate from the junction of the two. Alternatively, pick a mosfet with a higher Vgs rating but designed for 5V gate drive, such as TSM2313CX.
I will just omit C3. I didn't realize it was a problem. I added C1 thinking that was what you meant to do. C3 is just what I put next to all chips I use as a decoupling cap. I didn't know it was interfering with the P channel MOSFET. Thanks for explaining that. I kinda understand it now. I'll be sure to turn the h bridge signals off before turning off the P channel. Thanks!
On the same project, I need to turn off the Vcc to the DS3234 RTC chip. If I should start a new thread for that let me know. The 3 chips in my project are:Atmega328P-AU (first time to boot load the SMD variant)si9986 H-BridgeDS3234 RTCVcc for the Atmega328 & DS3234 is 4.5v (3 C cells)...trying to last a year on batteries, I will power down the Atmega328P, and have the alarm from the DS3234 interrupt wake it up. But if the DS3234 has Vcc it uses a lot of current. If I turn Vcc off, it uses only 1-2 uA from Vbatt (a coin cell battery). So I need to "disconnect" Vcc from the DS3234. Would this same technique I used on the si9986 work?